Yes, there are two bugs. The first with
[[gnu::access(write_only, 2)]]
int f(int n, char * a[n]);
And the second with -Wvla-parameter -Wno-attributes
[[gnu::access(write_only, 2)]]
int f(int n, char * a[n]);
int f(int n, char * a[n]);
Can you file two bugs? (if those don't exist yet)
Martin
Am Samstag, dem 14.12.2024 um 00:03 +0100 schrieb Alejandro Colomar:
> Hi,
>
> The diagnostic for the attribute directive ignored was due to an old GCC
> version. However, I'm still seeing diagnostics that I think don't make
> sense, with GCC 14.
>
> I think this is a compiler bug (or two), maybe?
>
> This seems to relate to array parameters; CC += Martin.
>
> Cheers,
> Alex
>
> alx@www:/tmp$ cat str.c
> #include <errno.h>
> #include <stddef.h>
> #include <string.h>
> #include <sys/types.h>
>
> [[gnu::access(read_write, 1)]]
> [[gnu::access(write_only, 4)]]
> [[gnu::null_terminated_string_arg(1)]]
> [[gnu::null_terminated_string_arg(2)]]
> inline ssize_t strsep2arr(char *s, const char *restrict delim,
> size_t n, char *a[restrict n]);
>
> // strsep(3) a string into an array of strings.
> // Return the number of fields in the string, or -1 on error.
> inline ssize_t strsep2arr(char *s, const char *restrict delim,
> size_t n, char *a[restrict n])
> {
> size_t i;
>
> for (i = 0; i < n && s != NULL; i++)
> a[i] = strsep(&s, delim);
>
> if (s != NULL) {
> errno = E2BIG;
> return -1;
> }
>
> return i;
> }
>
> alx@www:/tmp$ gcc -Wall -Wextra -S str.c
> str.c:10:16: warning: attribute ‘access (write_only, 4)’ positional argument 2 missing in previous designation [-Wattributes]
> 10 | inline ssize_t strsep2arr(char *s, const char *restrict delim,
> | ^~~~~~~~~~
> str.c:11:12: note: designating the bound of variable length array argument 4
> 11 | size_t n, char *a[restrict n]);
> | ~~~~~~~^ ~~~~~~~~~~~~~~~~~~~
> str.c:16:21: warning: argument 4 of type ‘char *[restrict n]’ declared as a variable length array [-Wvla-parameter]
> 16 | size_t n, char *a[restrict n])
> | ~~~~~~^~~~~~~~~~~~~
> str.c:11:21: note: previously declared as an ordinary array ‘char *[restrict]’
> 11 | size_t n, char *a[restrict n]);
> | ~~~~~~^~~~~~~~~~~~~
> str.c: In function ‘strsep2arr’:
> str.c:15:16: warning: attribute ‘access (write_only, 4)’ positional argument 2 missing in previous designation [-Wattributes]
> 15 | inline ssize_t strsep2arr(char *s, const char *restrict delim,
> | ^~~~~~~~~~
> str.c:16:12: note: designating the bound of variable length array argument 4
> 11 | size_t n, char *a[restrict n]);
> | ~~~~~~~~~~~~~~~~~~~
> ......
> 16 | size_t n, char *a[restrict n])
> | ~~~~~~~^
> alx@www:/tmp$ gcc --version
> gcc (Debian 14.2.0-8) 14.2.0
> Copyright (C) 2024 Free Software Foundation, Inc.
> This is free software; see the source for copying conditions. There is NO
> warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
>
>
>
>
